This agreement will facilitate collaborative research on issues of common interest to the NIAID Division of AIDS and Division of TB Elimination at CDC including the molecular epidemiology of drug resistance and TB treatment outcomes within the DAIDS sponsored International Epidemiological Databases to Evaluate AIDS (IeDEA) network and the DTBE sponsored Preserving Effective TB Treatment study network (PETTS), and parameters of TB drug efficacy such as drug resistance and drug pharmacology.